Short Answer:
Korean Martial Arts were started by the early settlers of the Chosen peninsula (modern day Korea).
Detailed Answer:
Although the early inhabitants migrated from China onto the Korean peninsula in small waves beginning more than 700,000 years ago, the earliest known settlements existed around 2333 B.C. The first established kingdom was founded in 57 B.C. It is believed that the soldiers of this early kingdom trained in grappling and hand fighting skills that became known as subak. By the 1st century A.D., there were three rival kingdoms. Kicking skills were developed, and called Tae Kkyeon. During the 7th century A.D., the elite youth of Korea were trained for social positions, and military leadership in a group called the Hwarang. These Hwarang Knights were taught combat skills such as unarmed fighting, stone throwing, weaponry, horseback riding, and archery, and had developed a warrior's code of conduct which is the foundation for modern Korean Taekwondo philosophy and tenets. Most of Korea's early Martial Art was inspired and heavily influenced by Chinese military training, but also developed with a philosophy, and blend of techniques and tactics unique to Korean culture.
During the Japanese occupation of Korea (1905 to 1945), and throughout World War II, native Korean Martial Art practice was suppressed, but survived through secretive training within remote villages. Koreans were forced to abandon teaching their own history and language, and were forced to learn Japanese. Some Koreans were permitted to study at Japanese Martial Art dojos, and learned Karate-do, Judo, and Aikido. Some Koreans also traveled to China, and studied various forms of ancient Chinese Martial Art.
In 1944, college professor Won Kuk Lee was the first to gain permission under the Japanese rulers to open a Korean Martial Art dojang (school) which he named Chung Do Kwan (school of the Blue Wave). Won Kuk Lee was the highest ranked student in Shotokan Karate-do under its founder, Gichen Funakoshi. Lee had also studied Tang Su Do (Chinese Hand), and had been introduced early in his life to the native Korean kicking of Tae Kkyeon through street fighters in Seoul who retained the ancient methods outside of formal structured training. After World War II ended, many annexed Kwans (affiliated schools) opened through Black Belt graduates of the Chung Do Kwan.
Some Koreans studied Japanese Judo, and developed a variation they called Yudo. Others studied Japanese Aikido, and developed a more brutal form of Korean Hapkido. Some Koreans during this time period revived the former native Subak, and Tae Kkyeon, while others pursued Chinese variations. During the Korean War (1950 - 53), the South Korean soldiers had developed their native Martial Art into a proven effective combat fighting system. By 1955, there were more than 30 Kwans in and around Seoul teaching Martial Art under various names. Some of the leading Martial Artists were pushing for unification, and a new name to identify the blend of ancient Korean kicking, grappling and hand strikes with the modern influences, while avoid reference to the recent unpleasant, and brutally abusive former Japanese occupation.
On April 11, 1955, a meeting was held where leaders of the largest civilian school (Chung Do Kwan), and the military Oh Do Kwan (former graduates of the Chung Do Kwan) gathered with prominent historians and political leaders to vote on a name. The name "Tae Kwon" was submitted on ballot, and selected by unanimous vote due to its meaning of using both hands and feet while resembling the former term of Tae Kkyeon (Kicking method). By 1961, the Korea Taekwondo Association (KTA) was established, and eventually, all of the various Kwans were ordered by the Korean government to unite under one leadership, bringing a variety of Martial Art skills under the umbrella term of Taekwondo. Nine main Kwans were recognized by the Korean government, numbered along with a 10th administrative Kwan to be united in the KTA. By November of 1972 the Kukkiwon (National Academy and World Taekwondo Headquarters) was completed in Seoul, South Korea.
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